Climate can influence the emergence and transmission of infectious agents and the specific mechanisms underlying the linkages between climate and infectious diseases vary widely. Many diseases are clearly sensitive to changes in humidity, temperature, precipitation and ultraviolet radiation intensity ( ). Among them are some of our planet’s greatest killers, such as malaria and cholera; others (e.g. Lyme disease, hantavirus, dengue fever), although less deadly, are still dangerously, debilitating. A first step is thus to define which characteristics make a disease or pathogen “climate sensitive”. Climate change can influence the epidemiology of infectious diseases by affecting the replication and movement of disease agents and vectors or can influence transmission dynamics indirectly through its effects on ecology or human behavior. As global temperatures continue to rise, there are growing concerns that climate change may produce serious adverse health effects. From 1889 to 1990, the global average temperature rose by 0.4-0.8C ( ) and there is a nine out to ten chance that global average temperatures will rise 4-7C by 2100, with longer and hotter summers and milder winters. However, to date, it is unclear to which extent climate change affect public health through waterborne infectious diseases.